Returns made to Lowe's, and the stuff from Pets and Ponds got here already!

Bulkheads, gravel, and loc-line pieces. The loc-line, handily enough, fit my two pumps' outlets, so they are now pushing water around in the 50G so I can get a feel for how much power I'm dealing with. Thus far, quite turbulent in there...the losses from pushing up the return piping should give me just what I need.